Artificial limb



H. 1. MORRIS.`

ARTIFICIAL LIMB.

APPLICATION FILED OCT. I. 1918.

Patented oet 26,1920.

fr 0 /9/1//3/27/ g" ta/ll CIlgENTOR Ezri 0N" UNITED srnrssy PATENT OFFICE.

HARRY J. MORRIS, OF KANSAS CITY, MISSOURI.

ARTIFICIAL LIMB.

Application filed October 1, 1918. Serial No. 256,383.

T 0 all whom t may concern:

Be it known that I, HARRY J. Mounts, a citizen of the United States, residing at Kansas City, in the county of Jackson and State of Missouri, have invented certain new and useful Improvements in Artificial Limbs, of which the following is a specifica-L tion.

Thisinvention relates to artificial limbs and more especially to ankle joint connections therefor, and has for its general object to render such connections more efficient. and to give foot movement very closely approximating the operation of the natural foot. 'f

lVith these objects in view the-invention consists in certain novel and useful features of construction and"combinations of parts as hereinafter described and claimed; and in order that it may be fully understood refV erence is to be had to the accompanying drawing, in which:l

Figure 1, is a central vertical section of the lower part of an 'artificial leg and the foot thereof, embodying the invention.

Fig. 2, is an invertedplan view of theV shank or leg portion ofthe limb.

Fig. 3, is a fragmentary verticaly section ofthe pivot of the ankle joint of the limb. Fig.4, is a detail perspective Yview of a partof the ankle joint construction.

In the said drawing, 1 indicates the foot and 2 the shank .of an artificial limb, the upper side of the formerl sloping Vdownwardly and forwardly at. the heel end' to a transverse semi-cylindrical recess 4 at theV axis of movement or ankle-jointpoinngthe said foot also having a' recess 5, in itsl upper side forward of said semi-cylindrical recess. Y

The heel portion is provided with a central opening 6, offset at its krear side-to accommodate an arm hereinafter described, and formed at the upper sideof said recess with a shoulder, shown in this instance as a cross pin 7 covered at its inner and lower sides with a strip of leather 8 or other sound-deadening material. An opening 9 extends from opening 6 to the bottom cf the foot, and is closed by a v'plate 10 fastened to the foot. and forming a supportfor a rubber or other elastic soundedeadening cushion 11, the foot being provided with a recess 12 to accommodate said plate 10 Vand other parts hereinafter mentioned, and said recess 12 is covered by the customary solev piece`13.

A centrally located bolt 14 extends through the foot forward of the opening 9 and radially from the semi-cylindrical recess 4, and is engaged within recess 12 by a washer nut 15. At its upper end said bolt is formed with or secured to a rock shaft 16 ournaled in a cylindrical shell or sleeve 17 fitted and secured in the lower end of the shank 2 of the limb, the said bearing sleeve or .shell having a slot 18 to accommodate the bolt 14 in the pivotal movements of the foot and shank, and to secure the bearing sleeve or shell in position, -a pair of bolts 19 extend upV through it and through the solid lower portion of the shank and are engaged with the hollow portion 20 of the latter, by retaining nuts 21.

A short bearing sleeve 22 lits over the centra-l portion of the sleeve or shell 17 and like the latter, is provided with a slot 23 to accommodate the bolt 14, and said sleeve 22 is secured rigidly to va swing arm 24 pro- Y jecting rearwardly and adapted for up and down movement within opening 6.. Said arm is provided with a socket or cap portion 25 receiving the'upper end of the elas-l tic or resilient cushion or'buffer 11, and terminates vin a vhook portion 26 for abutment against the covering of the cross pin 7 which thus serves as a strong and durable resistance or anchor for taking the strain imposed in compressing a spring `hereinafter identified, Vwhen the shank is swinging to and from a position slightly forward of that shown by full lines in Fig. 1. The arm 24 is equipped with a bolt 27 extending up f through a` bore or passage 28 in the solid portion of the shank and a recess 29 opening into the hollow portion of the shank,

Y and secured upon the upper end of the bolt is a flanged nut 30 for engagement with an` expansive coiledvspring 31 koccupying recess 29 and bearing at its opposite end against the solid portion ofthe shank. To compel the swing arm 24 to move downward when the weight of the wearer is applied on the heel,

a nut V82 secured upon the bolt 27, bears' against the'underside of the Vsolid portionv of the shank within the recess 83 thereof for the accommodation of the upperpart of the heelA of the foot, and a lock nut 34 is also mountedv on said bolt to guard against unscrewing movement of nut 32. The passage 2 8 should be suiliciently wide longitudinally of the foot, to permit the boltV 27 to have sidewise movementto accommodate the swing of the shank and arm 24,

and preferably should he pivotally connected as at 27a to arm 24 to give the best results in the action mentioned.

Assuming that the foot has just been placed flatly upon the ground, it will be apparent that the shank will occupy a downwardly and forwardly'sloping position as indicated by dotted lines, and that the resilient cushion ll will be under a heavy compression, it being noted that the thrust on the said cushion occurs because of the nut 32 bearing upwardly against the solid portion of the shank. As the leg straightens to a substantially vertical position as indicated by i'ull lines, the swing arm is relevated, the resilient cushion assisting in this operation. Immediately and uninterruptedly following the assumption by the shank of the last-named position, it swings forwardly so as to assume a slightly downward and rearward position, but as the arm 24: at this time is in engagement with the cross pin 7, this movement ofthe shank can take place only because the spring 31 yields to the downward pressure applied upon it by the flanged nut 30. As a result just as the shank attains such position that the foot should roll forward on the ball and toe preliminary to leaving the ground for a step, the pressure of the nut 30 on the spring 3l, is relaxed and said spring instantly reacts and causes the foot to simulate the corresponding movement of the natural foot and hence gives an impetus or momentum which enables the wearer to walk more naturally, with less fatigue, and more rapidly than would be possible where such resilient force was lacking.

From the above description it will be apparent that I have produced a construction embodyingthe features of advantage set forth as desirable in the statement of the object of the invention, and while I have illustrated and described the preferred embodiment of the invention, it will be understood that it is susceptible of modification without departing from the principle of construction involved or the spirit and scope of the appended claims.

I claim:

l. In an artificial limb, a shank portion and a Jfoot portion having an ankle joint pivotal connection, an arm projecting rearwardly from said connection and movable with the said shank portion and the foot portion having a downwardly disposed shoulder to limit upward movement of said arm, a sound-deadening elastic cushion for yieldingly resisting downward movement of said arm, and means for yieldingly resisting forward pivotal movement of the shank portion on the foot portion when said arm is in engagement with said shoulder.

2. In an artificial limb, a shank portion and a foot portion having an ankle joint pivotal connection, an arm projecting rearwardly from said connection and movable with the said shank portion and the foot portion having a downwardly disposed shoulder to limit upward movement of said arm, a sound-deadening elastic cushion for yieldingly resisting downward movement of said arm, a bolt extending upward from said arm into said shank portion, and resilient means interposed between said bolt and said shank portion for yieldingly resisting forward swinging movement of the latter when said arm is engaged with said shoulder.

3. In an artificial limb, a shank portion and a foot portion having an ankle joint pivotal connection, an arm projecting rearwardly from said connection and movable with the said shank portion and the foot portion having a downwardly disposed shoulder to limit upward movement of said arm, a sound-deadening elastic cushion for yieldingly resisting downward movement of said arm, a bolt extending upward from said arm into said shank portion, resilient means interposed between said bolt and said shank portion for yielding resisting forward swinging movement of the latter when said arm is engaged with said shoulder, and means mounted on said bolt and bearing against the shank portion to cause said bolt to move downward whenA downward pressure is applied upon said means by a relative rearward swing movement of the shank portion upon the .foot portion.

4r. In an artificial limb, a shank portion and a foot portion having a pivotal ankle joint connection, the foot portion having a f 1 downwardly disposed shoulder rearward of said ankle joint connection, an arm projecting rearwardly from the ankle joint pivot and bearing a pivotal relation thereto and adapted for arrest in its upward movement by contact with said shoulder, a resilient cushion underlying said arm for resisting downward movement thereof with respect to the foot portion, said shank portion having a bore and a recess communieating with the upper end of the bore, a bolt movable with and extending upwardly from said arm through said bore and into the said recess of the shank, a nut mounted on the bolt and engaging the shank to prevent downward swinging movement of the latter independent of said arm, a nut secured on the upper end of the bolt within said recess, and an expansive coiled spring occupying said recess and bearing at its lower end upon said shank and at its upper end against the underside of said last-named nut.

5. In an artificial limb, a foot portion having a semi-cylindrical recess, a recess forward thereof and an opening in the heel,

. means for resistin a shank fitting inthe recess forward of the semi-cylindrical recess and provided with a recess receiving the upper portion of the heel of the foot portion, a cylindrical shell f secured to the shank and fitting in the semicylindrical recess of the foot portion, and provided in its underside with a slot, a

short rock shaft journaled in said shell and yshell and also accommodating said bolt, an

arm projecting rigidly from said last-named sleeve and underlying and limited in its upward movement by the shoulder of the foot portion, a resilient cushion secured in the foot portion and exerting upward pressure on said arm, means whereby downward and rearward pivotal movement of the shank upon the foot portion, shall impart downward movement to said arm, and resilient forward pivotal movement of said shan upon the foot portion when said arm is engaged with said shoulder. 1

6. In an artificial limb, a foot portion having a semi-cylindrical recess and an opening in the heel portion, a shank fitting in the recess forward of the semi-cylindri cal recess and provided with a recess receiving the upper portion of the'heel ofthe foot portion, a semi-cylindrical shell extending transversely of the shank portion, a pair of bolts extending up through said shell .near its opposite ends and rigidly secured to said shank portion ;Vsaid shell having a slot in its lower portion centrally between said bolts, a short shaft within said shellbetween `said bolts and provided with a bolt extending downward through said slot of the shell and fastened rigidly to the said foot portion, a shortsleeve journaled on the shell between the said pair of bolts and provided in its underside with a slot registering with the slot of the shell and also accommodating the bolt of the said shaft, and also provided with a rearwardly projecting arm'occupying the said opening in the foot and under` lying the said shoulder of the latter, a resilient sound-deadening cushion secured to the foot portion and exerting upward pressure against said arm, means movable with said arm and pressing upwardly against said shank to transmit downward and rearward swinging movement of the latter to said arm, and resilient means for resisting forward swinging movement of the shank on the footportion when the said arm is in engagement with the said shoulder.

' In testimony whereof I affix my signature.

HARRY J. MORRIS. 

